The story goes that Lincoln might have changed "80 odd years" to "four score and ..." after seeing a rabbi's speech published in a Philadelphia paper/ journal.
July 4, 1863 was a Saturday, and Rabbi Sabato Morais, a Sephardi
immigrant from Italy serving as religious leader of Philadelphia's
Mikveh Israel Congregation, delivered his Sabbath morning sermon. His
sermon contains a phrase that might well have influenced the most
celebrated speech in American history.
http://www.huffingtonpost.com/marc-saperstein/gettysburg-address-jewish-connection_b_3539959.html
When Rabbi Morais wrote the speech, he did not know whether the
Confederates would break through Union lines and reach Philadelphia.
Choosing King Hezekiah's words during the Assyrian siege of Jerusalem:
"This is a day of trouble, of rebuke, and derision" (Isa. 37:3) to
reflect the mood, he alluded to the battle at Gettysburg some ninety
miles away. He continued, "I am not indifferent, my dear friends, to
the event, which four score and seven years ago, brought to this new
world light and joy."